http://www.oocities.org/SiliconValley/Peaks/8778/TAU_advprog.html
Advanced Programming Course - Exercise 1
To write a function "replace", which takes a string as
a parameter, replaces all spaces in that string by minus
signs, and delivers the number of spaces it replaced. To
print the result string and number. Thus
char cat[256];
strcpy( cat, "The cat sat");
/* strcpy - standard string copy function */
n = replace( cat);
should set cat to "The-cat-sat" and n to 2; these string and
number must be printed.